Many electrooptical products are made in large numbers which require many different operations. Electrooptic (EO) devices are those where an application of electronic stimulus leads to a change in optical property. The optical property can be optical density, color change, optical reflectivity change, or change in optical emission. For example in one product, one may require forming the shape of the product, coating and then followed by assembly. Some examples of such electrooptic products are lens and filter assemblies, automotive and motorcycle rear-view mirrors, displays and windows, solid state lights, etc. Some of the products are made efficiently and are available at attractive costs while others are done less efficiently. This innovation discloses methods of making EO devices in an efficient method. In addition many electrooptical devices require metallic layers that work both as conductors and optical reflectors. This innovation also discloses novel reflectors that have higher corrosion resistance to be used in EO devices that reduce manufacturing costs.
Digital video disks (DVDs) are produced inexpensively, although these require precision molding of two substrates, deposition of several layers of materials by physical vapor deposition, dispensing of glue, and assembly including 100% inspection. These are produced in line where the substrate formation is integrated with coating and assembly process in one equipment, with no manual manipulation of parts. Each of the processing steps is matched to the rates of the next step to avoid any accumulation and the molded substrates directly transition to the coating processes. As an example commercial rear-view mirrors are used in automotive and other transportation industry which are made in 10's of millions every year use two substrates with an electrochromic electrolyte sandwiched between them. However, the manufacturing processes are costly that end up in such mirrors being expensive. This invention lays out details of materials and processes for making inexpensive electrochromic (EC) devices for any application, and also other electrooptic devices that use two substrates with an electrooptic medium in between (e.g., liquid crystal devices) or require a number of coatings (e.g. organic light emitting diodes). For example, inexpensive manufacturing of EC rear-view mirrors will allow more consumers to benefit from the safety aspects of the EC technology. The inefficiency in making rearview mirrors comes in by mixing materials and processes in a way that they are separated by large batch processes. This results in large inventory between processes, and also addition of processing steps are used which would not be needed if there was no manual interruption/accumulation through the entire process. As an example, bent EC mirrors are made by slumping a stack of two sheets of glass so that their curvatures are matched. Thus one has to stack a large inventory of such glass sheets. Several mirror shapes are cut and each pair is marked so that when the final assembly is done this pair is assembled in the same orientation in which it was cut. This ensures uniform spacing between the two sheets which is later occupied by the electrolyte However, in the bending/cutting processes, cut chips and surface stains are formed, which need to be washed before coating. The washers are large, and again they require inventory buildup before and after. In addition the washing step consumes large amount of resources in terms of clean water and utilities for drying, and generation of waste water. Thus environmentally friendly methods that minimize the use of resources in manufacturing and do not generate waste are preferred. In this innovation it will be demonstrated that these issues can be overcome to make products using low cost manufacturing techniques, low labor costs and with smaller environmental footprint. Such methods are commonly used in DVD manufacturing but not used in electrooptic devices. For example, complete DVD production lines that integrate substrate molding, coating and assembly are available from Singulus Technologies AG (Germany). These methods may be used to form other EO products, e.g. those that emit light. For example, organic light emitting diodes can be made by forming the substrate and coating operations in one machine.